. >> a new warning if you drink a lost energy drinks, researchers used m.r.i. to image the hearts of 18 young adults before and after downing an energy drink and they caused the heart to squeeze harder although there was no change in the heart rate or blood pressure. more studies are needed to study the health effects of caffeine. >> trading is underway on wall street journal at 6:48. the big board shows over 16,000 mark but the dow is down 51 points. amazon and wal-mart are ready for cyber monday the busiest day of the year with sals predicted to reach close to $2 billion today and one in five shoppers will shop on a smartphone or tablet. overall spending for the black friday weekend is down 3 percent the first drop since 2009. >> amazon is testing delivery packages using drones. this is video of how the service works, delivering packans up to five pounds to customers living in a certain area. amazon hopes to have the project up and running in a few years. >> good thing they are not in action in the bay area because you could not see much because of thing for.